CPP Updates Classic Suspensions With An All-New Spindle Design

When GM muscle cars were new, the ride was relatively smooth, and they performed well – when driving in a straight line. Sure, they could handle the average corner when driving in town, or a long, sweeping bend on the highway while driving at the legal speed limit. But high-speed cornering was – at best – hopeful. And let’s face it, compared to modern cars, they’re infamous for having less than adequate factory suspension geometry.

With today’s technology available to enthusiasts to upgrade these antiquated designs, correcting those once barely adequate suspension features with performance-suspension upgrades like control arms helps. But, control arms and sway bars are only part of the optimum-handling equation. Classic Performance Products (CPP) has a firm grasp on building suspension parts that improve vehicle handling, and has introduced a new component to its suspension line that improves the now-obsolete factory geometry. CPP has done this by redesigning a crucial part of the suspension – the front spindle.

The CPP (PN: CP30013) spindle features a raised upper ball-joint mount to yield a better camber change during suspension movement. They also utilize factory bolt-in or CPP-replacement steering arms.

We collaborated with CPP engineer, Danny Nix, and Senior Tech guy Aaron Strietzel, to get the low down on this new assembly. “With trends heading toward the Pro Touring market, the use of sealed bearing hubs simply makes sense for use on a road course or for all-out performance applications. With our new CS spindles, we bring the performance of the maintenance-free hub design that is used on late-model Corvette applications (C5/C6/C7), and the usability of popular 13 and 14-inch disc-brake kits. These purpose-built spindles are available for all A, F, and X-body applications,” Aaron stated. [Spoiler alert: They will soon be available for popular full-size applications and in lowered ride-height versions as well.]

With trends heading toward the Pro Touring market, the use of sealed bearing hubs simply makes sense for use on a road course or for all-out performance applications. – Aaron Strietzel, CPP

More Than Just Parts

CPP’s improved CS spindle and hub assembly is not just a replacement piece for the sake of making a replacement piece. There is solid design and upgrade features that went into creating this part. For starters, factory-original hub/spindle assemblies were one-piece units. Since the CPP CS spindle uses a replaceable bearing/hub from a late-model Corvette, the big advantage of the CS spindle/hub is the sealed bearings. By using this Corvette, sealed-bearing hub assembly, you no longer need to continually grease and inspect bearings depending on how hard you push your car’s suspension. Since the assembly uses a Corvette hub, that also means any stock or aftermarket Corvette disc-brake kit will fit – limited by wheel size. The Corvette has a huge performance brake pad selection, and you can find replacement parts on the shelf in almost any parts store. That’s a huge benefit when it comes time for maintenance.

The spindle works with the factory C5, C6, and C7 Corvette hub/bearing pack, rotors, and calipers.

These CS spindles are a one-piece, ductile-iron casting. This keeps them very affordable, and eliminates the need for adding steel inserts at the ball joint locations, and special screw-in studs that required modifications to the hub. Although the CPP CS spindles come with a C7 bearing-hub, any C5, C6, or C7 hub will work without needing any modifications. The ’67 through ‘69 Camaro, ‘64-through ‘72 Chevelle, and ’68 through ‘74 Nova applications feature a raised upper ball joint location. The other CPP spindles retain the original geometry. Doing this keeps them compatible with all of your existing steering and suspension components.

“The spindle is cross-compatible with just about any product that is designed for use with the original spindle geometry. You can even utilize a tall upper ball-joint if you want,” Danny stated. Adding a taller-than-stock ball joint can increase negative camber-gain when cornering, which helps keep the tires flat on the pavement, greatly improving handling characteristics. “If you want to make any other changes to your steering or suspension, you can consider the CS spindle to be the same geometry as the OE spindle,” Danny said.

Braking Results

The Corvette hub assembly does have an attached ABS sensor, and that means there is a wire you have to contend with. If you are concerned about what to do with the unneeded ABS sensor that comes with the Corvette hub assembly, CPP also offers a C7 hub assembly that does not utilize the external ABS wire. The C7-sourced outer bearing is also larger than what is found on a C5 or C6. The new CPP spindle comes in designs that fit a wide variety of vehicles, as this is not a one-design-fits-all part. “It’s not like we made one and then modified the taper or throw in a different steering arm¸” Danny explained, “They are actually made specifically for every vehicle.”

The spindle is cross-compatible with just about any product designed for the original spindle geometry. You can even utilize a tall upper ball joint if you want. – Danny Nix, CPP

There are many hub options available, as the base kit uses a readily available, parts-store-grade bearing hub. Enthusiasts who wish to upgrade can order race hubs, and CPP can replace the 12mm wheel studs with high-grade, 1/2-20 SAE studs. As we said before, any bearing hub that is compatible with a C5 or later Corvette will work with these CS spindles.

Part number CP30014 is designed for second-gen F-body cars.

If you are wondering if there are any specific fitment options or areas to consider, the primary fitment concern is allowing enough space in the wheel for larger calipers. CPP has developed each of these kits so the company’s base brake kit will work. However, using larger diameter rotors and larger caliper bodies can become challenging. For example: a six-piston caliper from a C6 Corvette is 12 inches high when mounted, placing the caliper several inches higher than with any vintage OE spindle. When installing the CPP spindle and subsequent brake assembly, you would need to be careful about fitting this caliper between the upper and lower control arms, and insure adequate clearance throughout the full range of steering and suspension travel.

Big Bad Rollers

When it comes to wheel fitment, we’re told the wheel must be compatible with the Corvette brake caliper. They need to be at least 17 inches if using the 13-inch diameter rotors. Since these spindles are based on the C5 and later Corvette, there are a lot of different brake packages available. In the end, the wheel will need to be sized to the brake package being used.

While upgrading springs, sway bars, and even drum brakes seem to get all the attention, with help from Classic Performance Products, maybe it’s time we start realizing the benefits of updating the spindles on our classics. What have you got to lose, except an outdated suspension geometry, and antiquated, inferior braking technology.

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About the author

Randy Bolig

Randy Bolig has been working on cars and has been involved in the hobby ever since he bought his first car when he was only 14 years old. His passion for performance got him noticed by many locals, and he began helping them modify their vehicles.